The present invention relates to new reactive systems comprising a specific polyisocyanate component and a reactive component for this polyisocyanate component, as well as non-reactive plasticizers and if appropriate other auxiliaries and additives, and to a process for the preparation of polyurethane plastics containing isocyanurate groups using this reactive system.
The invention furthermore relates to new reactive systems which give two- or multi-phase shaped articles of good toughness, rigidity and heat stability after hardening.
The preparation of plastics containing isocyanurate groups has been known for years and is utilized industrially in diverse forms. DE-OS (German Published Specification) 2,534,247 thus describes, for example, a process for the preparation of moldings based on isocyanurate-modified polyurethanes using strongly basic compounds, such as, for example, alkali metal acetates or alkali metal phenolates, as trimerization catalysts.
Reactive systems which are based on epoxide/isocyanate (EPIC) components are described in a previous application by the applicant company in accordance with P 3 836 598.7. EPIC plastics (and epoxy resin) have good processing and hardening properties, and on hardening they give shaped articles of good mechanical strength, resistance to chemicals, and high glass transition temperatures, and undesirably high brittleness.
The invention was thus based on the object of developing EPIC resins which give shaped articles of improved toughness on hardening, can be processed as 2C materials, the metering of which causes hardly any mixing errors and which harden without noticeable shrinkage.